When and how to use a deacidifier?
Deacidification is best done as early as possible. Calcium carbonate is the most commonly used deacidifier. A great deal of frothing sometimes occurs on deacidification. You should therefore use a sufficiently roomy barrel/receptacle. Add the necessary quantity of deacidfier to the must, stir for a few minutes and leave to rest for a while. Stir again and once more leave to rest. Repeat this a few times until there’s no more CO2 formed (no sound of gas). Now leave everything to settle for 12-24 hours. Then siphon the must/wine, leaving the white layer at the bottom.